Synergistic Effects of Nanoporous Structure of Glassy Carbon Electrode and Electropolymerization of Catechol Film on the Electrocatalytic Oxidation of Hydrazine

Abstract

Non-precious metal-free electrocatalysts with high sensitivity, selectivity, and long-term stability, as well as extraordinary activity towards hydrazine (HZ) oxidation are challenging and desirable for various fields. Herein, a binder-free catechol (CC)-immobilized nanoporous GCE was conducted to electrooxidation of HZ at extremely low overpotential with fast response time (∼3 s). Owing to synergistic-assisted signal amplification between the CC and nanoporous GCE, and nanoporous GCE’s high-effective-surface-area for incorporation of CC within the pores of nanoporous structure, high sensitive detection of HZ along with long-term stability has been introduced. Moreover, binder-free modification resulting in increased accessibility of the HZ to active surface sites of the electrode, which in turn increased the electrode performance. The affecting factors on the anodic signal for determination of hydrazine were optimized by response surface methodology. An optimized limit of detection of 0.14 μM was obtained at a signal to noise ratio of 3 and a fast response time (∼3 s). Additionally, CC/GCE-red revealed higher sensitivity with two linear ranges from 0.3 to 8.6 and 8.6 to 120 μM. The suggested sensor’s promising qualities include its ease of manufacture and good stability of the modified electrode.